Panel joint assembly with drainage cavity

ABSTRACT

A joint assembly between a first panel and an adjacent second panel is disclosed. The first panel has a first exposed panel face and a female end on one end of the first panel. The female end of the first panel has a first end leg projecting inwardly from the end adjacent the female end of the first exposed panel face adjacent the female end of the first panel. The joint assembly has cooperating means on the male end of the first panel and on the female end of the second panel for preventing forward movement of the female end of the second panel 05 toward te first exposed panel face of the first panel. This cooperating means is also operable to prevent sidewise movement of the female end of the second panel away from the first end leg of the male end of the first panel, to allow for expansion and contraction of the female end of the second panel with respect to the male end of the first panel, and to positively position the female end of the second panel with respect to the male end of the first panel. The joint assembly has in addition a frame, fastening means for connecting the male end of the first panel to the frame, and either the male end of the second panel or the female end of the first panel covers the fastening means.

[ 1 Sept. 18, 1973 PANEL JOINT ASSEMBLY WITH DRAINAGE CAVITY [75] Inventor: Robert E. Thiele, Franklin Township, Pa.

[73] Assignee: United States Steel Corporation, Pittsburgh, Pa.

[22] Filed: Sept. 14, 1971 [21] Appl. No.: 180,335

[52] US. Cl 52/533, 52/538, 52/545,

52/546, 52/588, 52/537 [51] Int. Cl. E04c 2/52 [58] Field of Search 52/537, 538, 553,

Primary Examiner-Frank L. Abbott Assistant Examiner-Leslie A. Braun Att0rneyRobert J. Leek [57] ABSTRACT A joint assembly between a first panel and an adjacent second panel is disclosed.

The first panel has a first exposed panel face and a female end on one end of the first panel. The female end of the first panel has a first end leg projecting inwardly from the end adjacent the female end of the first exposed panel face adjacent the female end ofthe first panel. The joint assembly has cooperating means on the male end of the first panel and on the female end of the second panel for preventing forward movement of the female end of the second panel toward the first exposed panel face of the first panel. This cooperating means is also operable to prevent sidewise movement of the female end of the second panel away from the first end leg of the male end of the first panel, to allow for expansion and contraction of the female end of the second panel with respect to the male end of the first panel, and to positively position the female end of the second panel with respect to the male end of the first panel.

Thejoint assembly has in addition a frame. fastening means for connecting the male end of the first panel to the frame, and either the male end of the second panel or the female end of the first panel covers the fastening means.

1 Claim, 18 Drawing Figures PATENTED SEP] 8 I975 SHEET 3 [IF 5 PANEL JOINT ASSEMBLY wlru nnxmxcs CAVITY i BACKGROUND OF THE INVENTION Heretofore, metal siding has been produced with a variety of shapes and designs with various types of interlocking and retaining joint details. Most of these joint details provide a retaining function, interlock or method of providing for a hidden fastening device.

These panels may be attached directly to building walls m or sub girts.

Prior to my invention, metal siding joint details satisfied only the single interlock function and/or some other desirable feature or features. No such panel detail provided all of these desirable features or the multi- 1 plicity of featuresthe unique detail joint configuration of my invention provides.

l am aware of the following prior art patents:

The joint disclosed in US. Pat. No. 1,743,206 is exposed to view. Furthermore, the method of fastening is difficult and no provision is made for drainage of condensation. v

The joint disclosed in US. Pat. No. 3,142,937 is also 3 exposed to view, requires a clip fastener would be difficult to assemble,'provides pressure points onlyat the clips, and the rib is always extemaL' i I The joint disclosed in U.S. Pat. No. 3,394,519 requires a clip and the drainage, if any, would be ques- 40 tionabl ef Furthermore, it is only self positioned in two directions rather than in four directions.

U.S. Pat.'No. 3,41 1,25] relates primarily to a roof panel hold down means and with the design of the hold down means no provision is made for a continuous wall panel.

The joint disclosed in US. Pat. No. 3,438,168 is fastened by a clip held in place by a sheet metal screw and is not self positioning. Furthermore, it would not prevent movement back and forth unless fastened at one end. No provision is made for a simple sheet metal screw fastener.

OBJECTS OF THE INVENTION It is the general object of this invention to avoid and overcome the foregoing and other difficulties of and objeetions to prior art practices by the provision .of an improved wall panel joint assembly:

af having a joint which provides an interlock of two adjacent panels and which prevents side'movement or front displacement of one panel with respect to the adjacent panel; I b. has a joint which will provide drainage at the joint,

c. is self positioning with respect to an adjacent panel; v d. has a joint which will provide for a hidden fasten-. ing device;

e. ha s a joint which will provide for a sheet metal screw fastener or a snap clip fastener, both of g which are hidden; f. has a joint which will be aesthetically pleasing and not appear as a typical lock seam joint; I g g. has fastening means on only one end or edge of the panel thereby reducing the number of fastening devices and the cost of installation labor; I h. prevents forward movement of the female portion and sidewise movement of the female portion of the joint assembly with respect to the male portion of the joint assembly; and i. positively positions the female portion of the joint assembly with respect to the male portion of the joint assembly.

BRIEF SUMMARY OF THE INVENTION The aforesaid objects of this invention and other objects which will become apparent as the description proceeds are achieved by providing a joint assembly between a first panel and an adjacent second panel. The first panel has a first exposed panel face and a female end on one end of the first panel. The female end of the first panel has a first end leg projecting inwardly from the end adjacent the female end of the first exposed panel face adjacent the female end of the first panel. The joint assembly has cooperating means on the male end of the first panel and on the female end of the second panel for preventing forward movement of the female end of the second panel toward the first exposed panel face of the first panel. This cooperating means is also operable to prevent sidewise movement of the female end of the second panel away from the first end leg of the male end of the first panel, to allow for expansion and contraction of the female end of the second panel with respect to the male end of the first paneLand to positively position the female end of the second panel with respect to the male end of the first panel.

The joint assembly has in addition a frame, fastening means for connecting the male end of the first panel to the frame, and either the male end of the second panel or the female end of the first panel covers the fastening means.

BRIEF DESCIUPTION or The SEVERAL vnzws or THE DRAWINGS FIG. 1 is a top plan view of a panel (either a first panel or a second identical panel) and showing such panel provided with a first exposed panel face having a centrally exposed reinforcing rib and smaller opposed reinforcing ribs on either side of the centrally reinforcing rib; a male end on the right hand portion of the first exposed panel face having a first end leg extending inwardly from the right hand portion of the first exposed panel face and defining -with.a first retaining leg a socket; and a female end of the first panel on the left hand portion of the first exposed panel face having a second end leg projecting inwardly from the left hand end'portion of the first exposed panel face, and terminating in a second retaining leg having a first male protuberance on its left hand extremity;

FIG. 2 is a fragmentary top plan view of a typical joint assembly between a first panel and a second panel similar to the one shown in FIG. 1, and also showing the fastener contained within a pocket defined by the socket, the male protuberances omthe female end of the second panel and the first retaining leg on the male end of the first panel and where such fastener' extends through such first retaining leg and is hidden from view by the first male protuberance;

FIG. 3 is a view similar to FIG. 2 of an alternative embodiment of the joint assembly wherein the male protuberance on the female end of the second panel is arcuate in shape and the first retaining leg of the male end of the first panel is provided with a second cooperating means, such as a projection, for preventing sidewise movement of the female end of the second panel away from the first end leg of the male end of the first panel, to allow for expansion and contraction of the female end of the second panel with respect to the male end of the first panel and to positively position the female end of the second panel with respect to the male end of the first panel; further showing the female end of the second panel in dotted lines in its initial position prior to rotation into the final solid line position shown in this Figure; and also showing the fastener extending through the first retaining leg on the male end of the first panel into a sub girt, such as a C-beam, and the fastener being hidden by the second retaining leg on the female end of the second panel;

FIG. 4 is a view similar to FIG. 1 showing a panel having a first exposed panel similar to that shown in FIG. 1, a male end having a horizontally disposed socket and a first retaining leg having a male retaining rib, and a female end having a generally horizontal male protuberance on the end of the second retaining leg and the second retaining leg provided with a female retaining rib;

FIG. 5 is a fragmentary top plan view similar to FIG. 20f a joint assembly between two panels of the type shown in FIG. 4;

FIG. 6 is a perspective view partially cut away f clarity and showing a joint assembly of the type shown in FIG. and utilizing a clip to fasten the second retaining leg of the female end of the second panel to a sub girt such as a C-beam and utilizing a female retaining rib type projection;

FIG. 6A is a perspective view of the clip employed in FIG. 6, 'and FIG. 6B is a perspective showing an alternate type clip and having a female rib type cavity when the male retaining rib and female retaining rib are reversed in position;

FIG. 7 is a view similar to FIG. 1 of another alternative embodiment of a panel having on the male end a horizontal socket and a W-shaped cross sectioned male retaining rib! on the first retaining leg; and on the female end a generally horizontal male protuberance and a U-shaped .female retaining rib (having a flat end) on the second retaining leg;

FIG. 8 is a view similar to FIG. 5 of the joint assembly between two adjacent panels of the type shown in FIG. 7 and showingihe fastener extending through the point in the male retaining rib and hidden by the flat end por; tion of the female retaining rib; FIG. 9 is a view similar to FIG. 1 of another alternative embodiment of a panel having a male end provided with a horizontal socket and a- W-shaped pair of male retaining ribs separated by a flat surface; and the female end provided with a horizontal male protuberance and generally U-shaped emale retaining rib having a flat end surface on the second retaining leg;

and hidden by the flat female end portion of the female retaining ribs;

FIG. 11 is a view similar to FIG. 1 of another embodi v ment of a panel wherein the male end has a horizontah socket and the first retaining leg on the male end is pro-' vided with a clip means on its free end for engaging the portion of the second end leg of the female end of an adjacent second panel;

FIG. 12 is a view similar to FIG. 10 of a joint assembly between two adjacent panels of the type shown in FIG. 11;

FIG. 13 is a view similar to FIG. 1 of another embodiment of a panel having on the male end a horizontal socket and a generally V-shaped male retaining rib on the first retaining leg; and on the female end a generally horizontal male protuberance and a generally U- shaped female retaining rib on the second retaining leg;

FIG. 14 is a view similar to FIG. 12 of a joint assembly between two panels of the type shown in FIG. 13 wherein the V-shaped male retaining rib of the first panel is locked against the left hand sidewall of the generally U-shaped female retaining rib of the second panel; the fastener extends through the first retaining leg from the drainage cavity defined by the male retaining rib and female retaining rib; and such fastener is hidden by the. generally flat portion of the female retaining rib;

FIG. 15 is a view similar to FIG. 1 of another embodiment of the panel wherein the male end-is provided,

- male protuberance on its second retaining leg and a FIG. 10 is a view similar to FIG. 8 of a joint assembly generally Z-shaped second end leg extending outwardly from the left hand end of the first exposed panel face;

FIG. 16 is a view similar to FIG. 14 of a joint assembly between two panels of the type shown in FIG. 15.

Although the principles of this invention are broadly applicable to joints between adjacent wall panels, this invention is particularly adaptedfor use in conjunction with wall panels formed of a metal, such as steel, aluminum, or the like, plastic, wood, or the like, and joined to a sub girt such as a C-beam by means of a threaded fastener, clips, adhesives, or the like, and hence it has been so illustrated and will be so described.

DETAILED DESCRIPTION With specific reference to the form of this invention illustrated in the drawings and referring particularly to FIGS. 1 and 2, a first panel is indicated generally by the reference numeral 10. r

The first panel 10 has a first exposed panel face 12 (FIGS. 1,2) provided on its right hand end with a first endportion or male end 14 (FIGS. 1,2) and on its left hand end with a second end portion or female end 16 (FIGS. 1,2). For the purpose of strengthening the first exposed panel face 12, such first exposed panel face 12 isprovided with a centrally disposed male rib 18 (FIG. 1) flanked onopposite sides thereof by smaller reinforcing ribs 20aand 20b. Themale end 14 has a first en'd"leg 22 (FIGS. 1,2) extending inwardly from the first e'xposed panel face 12 and is provided with an angularly disposed socket 24 (FIGS. 1,2) adjacent its mid portions. A first retaining leg 26 (FIGS. 1,2) extends from the inner end of the first end leg 22 substantially parallel to the first exposed panel face 12 and extends outwardly from the right hand end of such first exposed panel face 12.

The female end 16 (FIG. 1) of the first panel has a second end leg 28 (FIG. 1) extending inwardly from the left hand end of the first exposed panel face 12, as viewed in FIG. 1. In addition, the female end 16 has a generally horizontal second retaining leg 30 (FIG. 1) extending outwardly from the left hand end of the firs exposed panel face 12 and terminating in a first male protuberance 32 (FIG. 1) which cooperates with the. socket 24 of an adjacent panel 10 as now described.

As shown in FIG. 2, the female end 16a of a second panel 10a is pivoted into position so that the second retaining leg 30a of the female end 16a of the second panel 10a rests against the first retaining leg 26 of the male end 14 of the first panel 10 and so that the male protuberance 32a on the second retaining leg 30a of the second panel 10a is fitted or locked in the socket 24 on the male end 14 of the first panel 10 thereby defining a drainage cavity 34 (FIG. 2). Fastener means, such as a screw type fastener 36 or the like, extends through the left hand portions of the first retaining leg 26 of the male end 14 of the first panel 10, as viewed in FIG. 2, into a web 38 of a C-beam type sub girt 40 to secure the male end 14 of the panel 10 to such C- beam 40 prior to the movement of the second panel 10a into the above described position. As shown in FIG. 2, the male protuberance 32a of the second panel 10a hides the fastener 36 from view.

The socket 24 on the male end 14 of the first panel l0'and the male protuberance 32a on the female end 160 of the second panel 10a form a cooperating means for preventing forward movement of the female end 16a of the second panel lfla toward the first exposed panel face 12 of the first panel 10. This cooperating means is also operable to prevent sidewise movement of the female panel end 16a of the second panel 101:

away from the first end leg 22 on the male end 14 of the first parie'l 10, to allow for expansion and contraction of the female end 16a of the second panel 10a with respect to the male end 14 of the first panel 10; and to positively position the female end 16a of the second panel 10a with respect to the male end 14 of the first panel.

ALTERNATIVE EMBODIMENTS It will be understood by those skilled in the art that alternatively, as shown in FIG. 3, a female end 16a of a second panel 10a may be joined to a male end 14 of a first panel 10 In this embodiment, the female end 16a of the second panel 10a has a first end leg 28 projecting away from the left hand end (FIG. 3) of a second exposed panel face 12a and terminating in a second retaining leg 30a extending generally horizontally away from the left hand end of the second exposed panel face 120 A male protuberance 32a having an end 14 of the'first panel 10 and so that the second retaining leg 30a rests against the spacer rib 44 projecting from the first retaining leg 26 on the male end 14 of the first panel 10.

The spacer rib 44 provides a pressure surface for the second retaining leg 300 on the female end 16a of the second panel 10a.

As shown in the left hand portion of FIG. 3, the drainage cavity 34 is defined by the first end leg 22 of the first panel 10 the socket 24, the retaining leg 26", the left hand portion of the spacer rib 44, and the male protuberance 32 on the end of the second retaining leg 30a. The fastener 36 is inserted through the right hand portions (FIG. 3) of the first retaining leg 26 and into the web 38 of the C-beam 40 and is hidden by the sec- 0nd retaining leg 30a.

As shown in FIG. 4, another embodiment of a first panel 10 is similar to the priorly described embodiments but the male end 14 is provided with a male retaining rib 46 on the first retaining leg 26 and the female end 16 of the first panel 10 is provided with a female retaining rib 48 on the second retaining leg 30. As shown in FIG. 5, the male protuberance 32 on the second retaining leg 300 on the second panel engages or is received in the socket 24 on the first retaining leg 26 of the first panel 10. The male retaining rib 46 on the first retaining leg 26 of the first panel 10 and the female retaining rib 48 on the second retaining leg 30a of the second panel 1011 form cooperating means for preventing the sidewise movement of the female end 16a of the second panel 10a away from the first end leg 22 of the first panel 10, allows for the expansion and contraction of the female end 16a of the second panel 10a with respect to the male end 14 of the first panel 10, and also positively positions the female end 16a of the second panel 101: with respect to the male end 14 of the first panel 10.

It will be noted from a consideration of FIG. 5 that the male retaining rib 46 on the first panel 10 and the female retaining rib 48a on the second panel 100 define a drainage cavity 34.

The fastening means (FIGS. 6,6A,6B) utilized to connect the first retaining leg 26 on the male end 14 of the first panel 10 to, for example, one of the flanges 50a,50b (FIG. 6) of the C-beam 40, in this case, the lower flange 50b is a clip 52 (FIGS. 6,6A). As shown particularly in FIGS. 6 and 6A, the clip 52 has a back portion 52a (FIG. 6A) and a central slot 52b from which a front member 52c (FIG. 6A) is bent to the left and provided with. a female retaining rib 52d (FIG. 6A) adapted to receive and engage the male retaining rib 46. As shown in FIG. 6, the top and bottom bifurcated portions 52e,52f are slipped under the edges of the top flange 50a and the bottom flange 50b respectively of the C-beam 40 to secure the first retaining leg 26 of the first panel 10 to the beam 40.-

It will be understood to those skilled in the art that while the female retaining rib 52d on the clip 52 is shown with a rounded end, it may also'be provided with a flat end.

Also, as shown in FIG. 68, if, for example, the C- beam 40 were discontinuous behind the male retaining rib 46 and-the female retaining rib 48 and the positions of the male retaining rib 46 and the female retaining rib 48 (FIGS. 4 and 5 and 6) were reversed, then a retaining clip 52 shown in FIG. 68 may be employed.

In a beam of tbe type shown in FIG. 7, the male end l4hu 7 of a first panel 10" is provided with a generally Trademark or Trade Name W-shaped male retaining rib 46 on the first retaining leg 22. The female end 16 of the first panel 10 is provided with a generally U-shaped female retaining rib 48 on the second retaining leg 30. In the joint assembly shown in FIG. 8, the fastener 36 is centrally inserted into the vee 49 in the male retaining rib 46 of the first panel 10 into the web 38 of the C-beam 40 and is hidden by the flat front portion of the female retaining rib 48a.

The alternative embodiment of a first panel 10 has on its male end 14' a male retaining rib 46 provided with two spaced prongs 56 separated by a flat surface 58' on the first retaining leg 26. As in the case of the embodiment of FIGS. 7 and 8, the female retaining rib 48 on the second retaining leg 30 on the female end 16 of the panel 10 is similar to the female retaining rib 48 shown in FIGS. 7 and 8. In FIG. 10, the fastener 36 extends through the flat portion 58 between the prongs 56 and is hidden by the female retaining rib 48a.

The further alternative embodiment of a first panel shown in FIG. 11 features a panel 10 having on its male end 14 clip means 60, suitably a C-shaped clip on the right hand end as viewed in FIG. 11 of the first retaining leg 26 on the male end 14 of such first panel 10".

In FIG. 12, the clip means 60 is disposed on the free end of the first retaining leg 26 on the male end 14 of the first panel 10 and is adapted to grip the top of the second end leg 28a on the female portion 16a of the second panel 12a to prevent sidewise movement of the second retaining leg 30a with respect to the socket 24" on the male end l4 of the first panel 10''.

The first panel l shown in FIG. 13 has a V-shaped male retaining rib 46 on the first retaining leg 26 on the male end 14". In the joint assembly of FIG. 14, the male retaining rib 46" is wedged against the inner left hand surface of the female retaining rib 48a and the fastener 36 extends through the first retaining leg 26 on the male end 14" of the first panel l0 and is hidden by the female retaining rib 480".

As shown in FIG. 14, the fastener 36 has its head located in the drainage cavity 34" and the fastener 36 is hidden by the female retaining rib 48a on the second retaining leg 30a on the female portion 16a of the second panel 10a.

The embodiment shown in FIG. 15 is similar on its male end 14 to the panel 10" shown in FIGS. 11 and 12. The female end 16" of such first panel 10 has the second end leg 28" formed in a substantially Z-shape to provide a narrow space D (FIG. 16) between the forward portions of the first end leg 22" of the first panel 10 and such second end leg 28a of the second panel l0a .'The drainage cavity 34 (FIG. 16) is provided either in the end space between the end of the male protuberance 30a and the end of the socket 24 or between the clip means 60 and the top end portions of the second end leg 28a of the second panel a.

It will be understood by those skilled in the art that the above described fastener means may be eithera fastener 36, a clip 52, or an adhesive, not shown, of the I following types:

Manufacturer SURLYN A ionomer resin E.l. du Pont de Nemours & Co.

"BAKELITE phenoxy resins PKHl-I and PAHJ SCOTCH-HELD" brand Union Carbide Corporation structural adhesives 3M Company I A-l103-B adhesive B. F. Goodrich Industrial Products Company uss NEXUS POE-l polymeric material United States Steel Corporation SUMMARY OF THE ACHIEVEMENTS OF THE OBJECTS OF THE INVENTION It will be recognized by those skilled in the art that the objects of this invention have been achieved by providing an improved joint assembly 10 (FIGS. 1,2, for example) having a joint which provides an interlock between two adjacent panels 10, 10a and which prevents side movement or front displacement of the second panel 10a with respect to the other planel 10; has a joint which provides a drainage cavity 34 at such joint; will be self positioning with respect to an adjacent panel 10a; has a joint which will provide for a sheet metal socket fastener 36 a clip fastener 52,52, adhesive or the like, all of which are hidden; has a joint which will be esthetically pleasing and not appear to be a typical box seam bond; has fastening means 36 on only one end of the panel 10 thereby reducing the number of fastening devices 36 and the cost of the installation labor; prevents forward movement of the female portion 16a of the second panel 10a and sidewise movement of the female portion 16a of the second panel 10a of the joint assembly with respect to the male portion 14 of the first panel 10 of the joint assembly; and positively positions the female portion 16a of the joint assembly with respect to the male portion 14 of the joint assembly.

While in accordance with the patent statutes, preferred and alternative embodiments of this invention have been illustrated and described, it is to be particularly understood that the invention is not limited thereto or thereby.

I claim:

I. A joint assembly between a first panel having a first exposed panel face and a male end on one end of said first panel, and a second panel having a second exposed panel face and a female end on one end of said second panel, said male end of said first panel having a first end leg projecting inwardly adjacent .said male end of said first panel, said female end of said second panel having a second end leg projecting inwardly adjacent said male end of said first panel, said joint assembly having:

a. cooperating means on said first end leg of said male end of said first panel and on said second end leg of said female end of said second panel for preventing forward movement of said female end of said second panel toward said first exposed panel face of said first panel;

b. said cooperating means on said first end leg of said male end of said first panel and on said second end leg of said female end of said second panel being operable to prevent sidewise movement of said female end of said second panel away from said first end leg of said male end of said first panel, to allow for expansion and contraction of said female end of said second panel with respect to said 'male end of said first panel, and to positively position said female end of said second panel with respect to said male end of said first panel;

' .c. a frame;

d..saidcooperating means having:

l. a first retaining leg on said first end leg of said male end of said first panel projecting from said first end leg of said male end of said first panel and said first end leg is provided with a socket projecting toward said first exposed panel of said first panel and opening inwardly toward said fe- ,male end of said second panel;

9 2. a second retaining leg projecting outwardly from said second end leg of said female end of said second panel and adapted to engage said first retaining leg of said first panel;

3. a male protuberance on said second retaining leg of said female end of said second panel adapted to engage said socket when said second retaining leg of said female end of said second panel enmale protuberance.

l l t 

1. A joint assembly between a first panel having a first exposed panel face and a male end on one end of said first panel, and a second panel having a second exposed panel face and a female end on one end of said second panel, said male end of said first panel having a first end leg projecting inwardly adjacent said male end of said first panel, said female end of said second panel having a second end leg projecting inwardly adjacent said male end of said first panel, said joint assembly having: a. cooperating means on said first end leg of said male end of said first panel and on said second end leg of said female end of said second panel for preventing forward movement of said female end of said second panel toward said first exposed panel face of said first panel; b. said cooperating means on said first end leg of said male end of said first panel and on said second end leg of said female end of said second panel being operable to prevent sidewise movement of said female end of said second panel away from said first end leg of said male end of said first panel, to allow for expansion and contraction of said female end of said second panel with respect to said male end of said first panel, and to positively position said female end of said second panel with respect to said male end of said first panel; c. a frame; d. said cooperating means having:
 1. a first retaining leg on said first end leg of said male end of said first panel projecting from said first end leg of said male end of said first panel and said first end leg is provided with a socket projecting toward said first exposed panel of said first panel and opening inwardly toward said female end of said second panel;
 2. a second retaining leg projecting outwardly from said second end leg of said female end of said second panel and adapted to engage said first retaining leg of said first panel;
 3. a male protuberance on said second retaining leg of said female end of said second panel adapted to engage said socket when said second retaining leg of said female end of said second panel engages said first retaining leg of said male end of said first panel; e. said socket and said first male protuberance defining a drainage cavity; and f. fastener means disposed in said drainage cavity and extending through said first retaining leg of said male end of said first panel and hidden by said first male protuberance.
 2. a second retaining leg projecting outwardly from said second end leg of said female end of said second panel and adapted to engage said first retaining leg of said first panel;
 3. a male protuberance on said second retaining leg of said female end of said second panel adapted to engage said socket when said second retaining leg of said female end of said second panel engages said first retaining leg of said male end of said first panel; e. said socket and said first male protuberance defining a drainage cavity; and f. fastener means disposed in said drainage cavity and extending through said first retaining leg of said male end of said first panel and hidden by said first male protuberance. 